Provided by the UCCI Observatory Dr. Wm. (Bill ) Hrudey 2012

Though the Dutch made the first telescope in 1609, it was Galileo who in 1610 improved the design and generally receives credit as being the first.

In 1670, Johannes Hevelius built this 150 foot long refracting telescope in Danzig.

In 1789, Sir Wm. Herschel built this 40 foot long telescope in Slough, England. It’s size and weight limited its use.

In 1845, Lord Rosse completed this 6 foot diameter reflector telescope in Ireland which he used to discover the first spiral galaxy.

In 1897, the Yerkes 40 inch refractor telescope was completed and remains the larges refractor telescope

The Mount Wilson 100 inch reflector telescope was completed in Edwin Hubble’s work in 1924 on the Andromeda galaxy and subsequent studies regarding expansion of the universe were done here.

Opened in 1948, the Hale (Palomar) 200 inch telescope was a modern marvel of engineering – read “The Perfect Machine” by Ronald Florence.

Hubble was launched in 1990 and, despite initial growing pains, proved to be revolutionary in the images it produced. Most notable were the Hubble Deep Sky images next.

This Hubble photo taken over a 5 month period beginning in September 2003, covers an area 1/13,000,000 of the total sky and represents the appearance some 13 billion years ago. Some additional 10,000 galaxies were found in an otherwise empty segment of space.

Others – some of many: Large Binocular Telescope in Arizona Large Synoptic Survey Telescope in Chile Keck Observatory in Hawaii

Amazing others: Chandra X-ray Observatory 1999 Solar Dynamics Observatory 2010

Refractor telescope Reflector Variation of reflector Schmidt – Cassegrain - Maksutov

Pros: Easy to use Good image if optics good Sealed tube Cons: More expensive Usually high f/ Heavier/bulkier for given size

Undesirable Desirable

Pros: Lower cost than refractor Best for DSO Low in aberrations Cons: Open tube More maintenance

Problem resolved if curve is paraboloid vs. spherical Desired - normal Aberrant - undesirable

Alt/Azimuth English yoke German equatorial Fork mount Split ring

The telescope polar axis is parallel to the earth’s axis. Thus, as the earth rotates west to east, the telescope rotates in the opposite direction to track object ie: keep it in the FOV. The angle of the polar axis above the horizon is equal to the latitude of the telescope location.

Amateur Telescope Making – 3 vols. Mechanix Illustrated in the 50’s Stellafane - Springfield, VT Amateur Telescope Making – 3 vols. Mechanix Illustrated in the 50’s Stellafane - Springfield, VT

Grinding and polishing your own mirror.

…. came along and built good consumer telescopes for reasonable prices. Very few amateurs bothered to build their own scopes. ATM became a lost art.

Essential features: Simple Alt/Az mount Thinner but larger mirror Portable and good for DSO’s Sonotube construction to trusstruss tube for larger

Dobsonian mount: Eyepiece holder: Mirror & diagonal: Mirror cell:

Optics:6” diam. Paraboloid mirror Diagonal mirror Eyepiece holder & eyepiece Mirror cell – will make Tube:8” OD x 48” long Sonotube Mount:¾” plywood, paint, hardware Finder:Televue or equivalent Estimated cost of above – <KYD$300 Patience, patience and more of same. Simple tools – Bill will help with the difficult areas

¾” Plywood$ 20 ½” Plywood$ 5 Plastic laminate$ 5 8” Sonotube$ 8 Primary /secondary mirrors$150 Eyepiece 8 – 24 mm Zoom$ 65 Eyepiece holder – make$ 10 Primary mirror cell – make$ 10 Total:$ 273 Hardware, paint, shipping extra.

1: Center the secondary mirror on the axis of the focuser drawtube. 2: Aim the eyepiece at the center of the primary mirror. 3: Center your primary mirror's sweet spot in the eyepiece's field of view.

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